Pourchaire, the 2022 series runner-up, collided with Ollie Bearman on lap seven while attempting to pass Martins down to Turn 1, outbraking himself and crashing into the side of the Prema.
The ART Grand Prix driver was seen going over to the Ferrari junior to apologise after the crash, which prompted a safety car, while Bearman said over the radio "this guy is crazy."
Reigning F3 champion Martins narrowly avoided the incident, going on to finish second in the race, but said his team-mate "came way too fast" on the approach to the corner.
Speaking after the race, Martins said: "I was going quite fast, I braked quite late, and then I stayed on the line and I saw Theo going like really, really fast into Bearman.
"So I was like that was a mistake, because I was already going really, really fast, and I was catching the others on the braking, and he came way too fast.
"So I don't know, I think he needed to stay a bit more calm, because we have good pace and we can come back later in the race."
Asked whether he was worried about getting caught up in the incident, Martins added: "He just braked maybe a bit too late and he lost probably the rear.
"I saw him coming at the end of the brake and I just opened the wheel and braked a bit more to wait and to see what was going to happen.
"When I saw he hit Bearman, for sure I was in a mist, I was not understanding everything, I had to maybe go right, maybe go left.
"I saw they were going a bit on the outside so I kept my line and that was it."
Saturday's second-place finish was Martins' second podium in three races, having finished third in the season-opening sprint race in Bahrain.
Pourchaire had been leading the standings before the sprint race, but has now been passed by Ralph Boschung, who finished fourth.
Martins said the experience he gained from two years each in Formula Renault and F3 respectively has helped him to manage his emotions in chaotic races such as Saturday's.
Ahead of the season starting, ART boss Sebastien Philippe said Martins had "pretty much all" the maturity required for his rookie F2 campaign.
Martins said: "I will say my experience paid off today, being calm and managing every situation.
"Like in the moment, with a lot of thinking before doing, and also to prepare everything, prepare as much as possible and drive in the moment instinctively.
"When you know what is the target, you always know and you do it naturally if you need to be aggressive, if you need to be calm, if you need to be defending or not, and all those things.
"I think I got so much experience from so many years in Formula Renault and Formula 3, as he said I think I got a lot of maturity, I know how to manage myself, manage my emotions throughout the race.
"I'm happy about today's race, in the past I would have tried everything to win the race but maybe I would have had something bad.
"So I'm really happy I grew up as a racing driver and as a person in life and I think all the years I have done are paying off right now."
